Focused-Electron-Beam Engineering of 3D Magnetic Nanowires

Abstract

Focused-electron-beam-induced deposition (FEBID) is the ultimate additive nanofabrication technique for the growth of 3D nanostructures. In the field of nanomagnetism and its technological applications, FEBID could be a viable solution to produce future high-density, low-power, fast nanoelectronic devices based on the domain wall conduit in 3D nanomagnets. While FEBID has demonstrated the flexibility to produce 3D nanostructures with almost any shape and geometry, the basic physical properties of these out-of-plane deposits are often seriously degraded from their bulk counterparts due to the presence of contaminants. This work reviews the experimental efforts to understand and control the physical processes involved in 3D FEBID growth of nanomagnets. Co and Fe FEBID straight vertical nanowires have been used as benchmark geometry to tailor their dimensions, microstructure, composition and magnetism by smartly tuning the growth parameters, post-growth purification treatments and heterostructuring.

Expanding FEBID-Based 3D-Nanoprinting toward Closed High-Fidelity Nanoarchitectures

“…In particular, slow lateral movement is the key for real 3D architectures as subsequent nanovolumes get vertically deposited with a small lateral displacement. This approach is denoted as 3D-FEBID (or 3D-nanoprinting) and allows additive, direct-write fabrication of even complex geometries and therefore evolved into a very powerful and flexible 3D-nanoprinting technology with applications in nanomagnetics, , plasmonics, and nanoprobe fabrication for scanning probe microscopy, , to name a few. In the past, however, most fabricated 3D structures were meshed or wireframe-like , meaning individual nanowires, which are connected at specific points in 3D space to form certain target structures .…”

Controlled Morphological Bending of 3D-FEBID Structures via Electron Beam Curing

“…The navigation of the electron beam in the XY-plane and the precise adjustment of the dwell times (deposition times in each individual position) ultimately generate the deposit morphology [ 17 ]. Especially 3D-FEBID, where true three-dimensional architectures are built via slow lateral movements, is a very powerful tool that enables novel application concepts for plasmonics [ 12 ], nanomagnetics [ 18 , 19 , 20 ] and 3D-nanoprobe fabrication for scanning probe microscopy [ 21 , 22 ], among others. The technique that was mainly used to build mesh-like structures in the past [ 23 , 24 ], was recently expanded to closed or sheet-like objects, which strongly improved its options in terms of design flexibility [ 25 , 26 , 27 , 28 ].…”

Magnetic Functionalization of Scanning Probes by Focused Electron Beam Induced Deposition Technology

“…This development has been focused on the optimization of thin magnetic patterns in 2D. More recently, the investigation has been extended to 3D FEBID magnetic deposits [33][34][35], spurred on by promising applications in scanning probe techniques, such as Magnetic Force Microscopy (MFM) [36] and Magnetic Resonance Force Microscopy (MRFM) [37], racetrack-type magnetic memories [14], Hall sensors [11,22], nanomagnetic logic circuits [36,38], superconducting vortex lattice pinning [39], remote magneto-mechanical actuation [40], etc. However, whereas FEBID flexibility allows the production of challenging structures with sophisticated geometries [7,10,12], many applications can be based on the simplest objects, such as vertical straight nanowires.…”